1.3 μm VCSELs for fiber-optical communication systems

Optical data transmission will greatly benefit by taking the step from the transmission wavelength of 0.85 μm to 1.3 μm, since this will allow a much extended transmission distance at high data rates as well as greatly enhanced eye-safety. Vertical cavity surface emitting lasers (VCSELs) are key components for low-cost systems (such as Gb Ethernet). This paper therefore addresses the status of VCSELs emitting around 1.3 μm. The various approaches based on both GaAs- and InP-based active regions will be outlined and their respective advantages and drawbacks will be discussed. At present, devices based on InGaAsN-GaAs quantum wells offer the highest promise due to their superior optical output powers at both room temperature and at elevated temperatures. At the same time they benefit from the utilisation of standard GaAs/AlAs VCSEL technology.